|
|
|
I pulled the airbox on a'93 240 in order to check the hot air thermostat. The thermo was OK, but I popped in a new one anyway, how long can one possibly last?
While in the airbox, I noticed the air damper seal was queefed out. Can anyone recommend a suitable, readily available material from which to carve a new one?
I know I might be able to get a seal from Volvo, but that would be at least one week away, even if all the planets fall into alignment. Also, McMaster-Carr probably has something usable hiding in their catalog, but I would like something here and now so that I do not have to suffer the PITA of buttoning it up just until the parts arrive.
Any possible sources for a gas-resistant, closed-cell foam would be appreciated.
If I can't source something locally, I might go with some 1/8" thick felt I have on hand.
Rich (near The Burgh)
|
|
-
|
|
|
Thanks one and all for the good info.
I ended up cutting a seal out of some material I have used when renewing Vanagon heater boxes.
The material is Duck brand Pipe Wrap Insulation. It is what appears to be felted synthetic fiber, 3" wide and, curiously, 1/11" thick. The roll was originally 25 ft. long. I most likely picked it at a hardware.
I cut two rings 3" on the OD, 1 1/2" ID and slipped them, stacked, over the seal flange of the damper. A 3 1/8" OD would have been perfection, but 3" provided an ample sealing surface.
If my sweetheart never complained about her car driving "funny" on cold mornings, I would have eliminated the hot air intake. I did that on my son's car - the fewer things on a car for him to ignore, the better.
Rich (near The Burgh)
|
|
-
-
|
|
|
Once again, Art, thanks for some great photos. Now, if ever I need some granulated copper . . .
Sure wished those thermostats would fail in the closed (or is that opened?) position.
Curious, I too dissected one. The actuator pin was frozen in place, so I went at the autopsy by wasting away the body of the thermo against a disc sander. I must be getting smarter in my old age because I figured that since I had now idea what was in one of those things, I had better don my grinding shield,
When I breached the case, it gave out a slight psssst and an oil mist. Kinda anti-climatic, but you never know. I learned long ago, whenever you venture into the unknown, wear eye protection.
Rich (near The Burgh)
|
|
-
posted by
someone claiming to be CB
on
Sat Mar 4 23:08 CST 2017 [ RELATED]
|
|
all that.
on my 87
when the Winter is Tempu Wize consistantly below 25Deg
I hook up the connctor between the exhaust and that long corrigated thingy
When it ain't too cold, I don't. Yeah I got a functioning Thermo in the Box
Simple
|
|
-
|
|
'fraid I'm one of those who might just as soon pin it shut and make no effort to restore the preheat function. But as a general answer, I think you can find various thicknesses of closed-cell foam with adhesive backing in the weatherstrip area of the hardware stores.
http://cleanflametrap.com/airbox.html
On the topic of AMM deterioration, I've been marking mine with the resting voltage output, measured after cleaning the connector and assuring myself the ground, while operating is no more than 50mV above the battery terminal. Those over 1.4V at rest seem to be goodies.
--
Art Benstein near Baltimore
Engineering says: "The designs are well within allowable limits"
Engineers meant: We just made it, stretching a point or two.
|
|
-
|
|
|
Many people remove the hot air flapper and the thermostat valve actuator and seal off the hot air intake permanently. Keeps the AMM from getting cooked when the thermostat inevitably fails. I've noticed no appreciable loss in performance from this mod, although the engine takes slightly longer to warm up when very cold, and I suspect it affects emissions during the warmup period.
|
|
-
|
|
Yeah, that flappy valve foamy seal from the original factory run will have decomposed on all of them.
Preheat on an 850:
https://volvo850wagon.wordpress.com/2014/11/30/110-preheat-air-valve-stuck-affects-maf-sensor/
I guess you could find some sort of silicon material to cut a piece that is compliant (soft) enough to seal to the preheat warm air inlet spigot doo-hickey inside the air box. Or flat foam? Something to seal with thermal qualities and use some adhesive that works for the application. Some research on your part. McMaster-Carr or ??? Some sort of gasket you can trim to fit and adhere to the air flappy valve.
Unless PA-state performs a visual inspect at emissions test time, you may be able to do without the preheater hose and the thermal-statically controlled flappy valve assembly. Leave the lower air inlet hole open. As I've done.
The thermostat-controlled flappy valve continues to let in warmed air at cold and colder temps with the engine warmed. It gets closed yet lets in an amount of preheat mixed in the air filter box for the AMM hot wire or film to encounter. Not merely for shortened warm-up times. Maybe the AMM/MAF, in cold climes, needs the preheat to work as the AMM has limits on how cold the inducted air can be.
Even with the engine warmed, warming the engine bay, at speed, the inducted air would not have much time to draw heat through the air induction up to the throttle.
I'm unsure how, with flappy-valve assembly removed, perpetually cold air across the heated AMM wire, or film (ribbon affects how atmospheric mass is measured. If it loses accuracy or not and can futz up fuel economy or worse. Such as with very cold air. Could it overwhelm the heated wire? If the airbox with exhaust manifold preheater is all there, maybe we do the engine control a disservice removing it?
Would fuel from the injectors become vapor at extreme cold. Does it have an deleterious effect on combustion for those of us, like me, that has removed the air filter box flappy valve assembly?
The latest K-Jet equipped models had one in the 1980s. I don't recall any on a k-jet equipped 1070s model.
Could there be need of keeping the butterfly valve in the throttle assembly warmed, also? Even cleaned, there is a petroleum glaze. Could one encounter a frozen throttle if extremely cold with high relative humidity?
I kept the flappy valve assemblies and can restore them. Though without some sort of seal, they'd always let in some preheat air.
Though without the flappy valves, and both air inlets open, you get a little more throttle response. Just.
Probably articles to read about it by those in the know.
Hanging Out Down by the Brickboard Sat-Your-Day Night, Speculatin'
|
|
|
|
|
